ATCA is an open industrial standard architecture stipulated and developed by the PCI Industrial Computer Manufacturers' Group, and is designed as universal hardware platform technologies for both telecom devices and computing servers. Various telecom devices and computing servers that meet different requirements can be built by various modules based on the ATCA standard. ATCA generally refers to the PICMG 3.x series standards, including specifications of shelf structure, power source, heat dispersion, single board structure, backplane interconnection topology, system management, switch network proposals, etc. ATCA in broad sense includes specifications made by PICMG, such as ATCA, ATCA 300 and MicroTCA.
Intelligent Platform Management Interface (IPMI) specification is an intelligent platform management interface standard proposed by some big computer communication companies for improving servers' usability, which is to provide the servers with functions like device management, sensor/event management, user management, fan shelf/power shelf management, remote maintenance, etc.
PICMG 3.0 defines the IPMI specification as a management specification that ATCA abides by. A block diagram of the principle of single board power control based on IPMI management specification is shown in FIG. 1, in which Intelligent Platform Management Controller (IPMC) and Intelligent Platform Management Bus (IPMB) are both management components defined in the IPMI specification. The power conversion/control module is configured to receive backplane power input and complete conversion of management power and load power that the board needs, where the management power is supplied to management related circuits like IPMC, etc., and the load power is supplied to the load circuit. After the single board is plugged into the backplane, the power conversion/control module does not supply a management power under control; the IPMC is powered on and starts to work normally. At this moment, the load power is not supplied. When certain conditions are met, the single board IPMC communicates with Shelf Manager via Intelligent Platform Management Bus (IPMB); after getting permission from the Shelf Manager, the single board IPMC enables the ENABLE signal of the load power of the power conversion/control module, which in turn supplies load power to the load circuit.
The structure of an ATCA single board is shown in FIG. 2. The ATCA specification defines two types of single boards: Front Board (FRB) and Rear Transition Module (RTM). The connector at the backplane side of the ATCA single board is divided into three zones: Zone 1, Zone 2, and Zone 3. The Zone 1 connector provides power and management plane signals for the front board. The Zone 2 connector provides the Front Board with control plane signal, data plane signal and clock signal. The Zone 3 connector is used for user-customized connections. The front board is plugged into the ATCA shelf from its front, and is connected to the backplane via the Zone 1 and Zone 2 connectors, including the connection of a power source with a signal. The Rear Transition Module is plugged into the ATCA shelf from its back, and is connected to the corresponding Front Board via the Zone 3 connector, including the connection of the power source with the signal.
In FIG. 2, two handles, a top handle and a bottom handle, for facilitating the plugging/unplugging of the single board, are installed on both the FRB and the RTM. A handle switch is mounted at the position of the bottom handle of the Front Board. The handle switch is in different states when the bottom handle is opened or closed. The IPMC on the FRB can recognize whether the bottom handle is open or closed by detecting the state of the handle switch signal that is coupled to the handle switch. The transition of the handle state is a key element in the transition of operating states of an ATCA single board.
The ATCA single board has different operating states during its operation. FIG. 3 shows the transition of the operating states of the ATCA single board. As shown in FIG. 3, the single board is in M0 state when it is not completely plugged into the ATCA shelf backplane. The board is in M1 state when it is completely plugged into the backplane but the handle is not closed, at which moment management power is supplied to the single board, related circuits like the IPMC, etc., are powered on and start to work, while load power is not supplied, and the single board is not activated. After the handle is closed, the single board enters M2 state, IPMC detects, via the handle switch signal, that the handle is closed, and starts to announce to the Shelf Manager that the single board is in position, and requests the shelf manager to activate the single board, when the request is permitted, the board enters M3 state; in M3 state, IPMC negotiates power with Shelf Manager, after getting permission from the shelf manager, IPMC controls the power conversion/control module to supply a load power, the other parts of the single board are powered normally; after the single board is activated, it enters M4 state, i.e. its normal operating state. Unplugging of the single board is the reverse of the plugging. In the unplugging process, the transition of the handle state is also a key element in the transition of operating states of the single board.
FIG. 4 is a block diagram of power supply to the RTM in the present ATCA system. The RTM power is supplied by the load power branch which is supplied by the FRB power conversion/control module, and via Zone 3 connector to the RTM circuits, which include an RTM management circuit and an RTM load circuit. The processes of plugging/unplugging and powering-on of the RTM are as follows:
In the process of hot swap of the single board, it is necessary to avoid current rushes. The RTM current supplied by the FRB via Zone 3 connector to the RTM is relatively high, and therefore, the RTM power supply needs to be cut off while the RTM is plugged in. One way is to plug in the FRB before plugging in the RTM. Other way is to plug in the RTM first with the handle open, at this moment, since the IPMC of the FRB does not detect that the handle is closed, it stays in M1 state; the power conversion/control module does not supply load power, and therefore the RTM is not supplied with power. After the plugging and connection of the FRB and RTM are completed, the handle of the FRB is closed, and the IPMC starts to communicate with the Shelf Manager via the IPMB. During the power negotiation process, the IPMC considers requests for power supply, from both the FRB and RTM, after getting permission from the shelf manager, it enables the load power “enabled” signal of the power conversion/control module to permit it to supply the load power, and meanwhile the RTM also obtains its power supply. In the process of unplugging the RTM, the FRB handle needs to be opened first, the single board should be deactivated according to the deactivation steps described in FIG. 3, and the RTM can be normally unplugged, only after both the FRB load power and the RTM power supply are cut off.
The ATCA300 standard defines a telecommunication hardware platform architecture, which is stipulated by the PICMG based on the ATCA standard for 300 mm-depth cabinets. In order to meet installing requirements of 300 mm-depth cabinets, in the ATCA 300 standard, some modification is made on the size of the FRB; the RTM in the ATCA standard is removed; and a Front Transition Module (FTM) that has similar applications to the RTM is added. In the ATCA 300, the FRB and FTM are connected with the backplane via the Zone 3 connector of the FRB and the Zone4 connector of the FTM, as shown in the ATCA 300 board scheme of FIG. 5.
As shown in FIG. 5, the FTM is substantially similar to the RTM in the ATCA, except for its location in the shelf and the connection with the FRB. The power management for the FTM is also the same as that for the RTM, which is not elaborated here. In order to simplify the description, the RTM/FTM is used to represent the RTM or FTM in this description.
The FRB power conversion/control module supplies the FRB load power and RTM/FTM power, and does not support independent and flexible management and control of power supply of the RTM/FTM, or hot swap. That is, in the process of plugging/unplugging the RTM/FTM, the FRB load power needs to be cut off, which interrupts the operation of the FRB.
Additionally, in general, the FRB presets the RTM/FTM power supply according to the design of the RTM. Therefore, the power may not be utilized efficiently according to the actual power consumption of the different RTM/FTMs plugged; and the power resource is wasted.